Graphite is a laminated body formed by laminating exfoliated graphite. By peeling graphite, a graphene-like carbon material such as exfoliated graphite having the number of lamination smaller than graphite, graphene or the like is obtained. Since the graphene-like carbon material excels in conductivity and heat conductivity, application to a conductive material, a heat-conductive material and the like is expected.
Moreover, a resin composite material is also formed by forming a composite of a graphene-like carbon material with a resin or the like. For the purpose of increasing affinity of a graphene-like carbon material for a resin or the like, it is known that the graphene-like carbon material is modified. For example, Patent Literature 1 discloses a denatured carbon material in which a fragment obtained by radical decomposition of an azo radical polymerization initiator containing carboxyl groups is added to a carbon material having a graphene sheet structure.